Benjamin I. Chung, MD

Associate Professor of Urology at the Stanford University Medical Center

Bio

Bio

Benjamin I. Chung, MD is a Urologic Oncologist specializing in the treatment of prostate and kidney cancer. As Director of Robotic Surgery, he has one of the largest surgical experiences in robotic prostatectomy and robotic kidney surgeries in the Bay Area and his excellent outcomes have resulted in his election to Castle Connolly Top Doctors and Best Doctors in San Francisco.

Dr. Chung's research focuses upon improving outcomes of surgical management of urologic cancers and in better understanding the causative factors in the formation of these malignancies to allow for future preventative action.

Links

Research & Scholarship

Current Research and Scholarly Interests

Dr Chung is interested in outcomes and epidemiology of renal cell carcinoma and carcinoma of the prostate. He is also developing new technologies in the treatment of both prostate and kidney cancer. He is studying the efficacy of minimally invasive laparoscopic techniques for kidney tumors, including cryotherapy, and in developing robotic and laparoscopic novel therapies in the treatment of prostate cancer.

This pilot clinical trial studies perfusion computed tomography (CT) in predicting response
to treatment in patients with advanced kidney cancer. Comparing results of diagnostic
procedures done before, during, and after targeted therapy may help doctors predict a
patient's response to treatment and help plan the best treatment.

The Prostate Active Surveillance Study (PASS) is a research study for men who have chosen
active surveillance as a management plan for their prostate cancer. Active surveillance is
defined as close monitoring of prostate cancer with the offer of treatment if there are
changes in test results. This study seeks to discover markers that will identify cancers that
are more aggressive from those tumors that grow slowly.

This clinical trial studies ultrasound elastography in diagnosing patients with kidney or
liver solid focal lesions. New diagnostic procedures, such as ultrasound elastography, may be
a less invasive way to check for kidney or liver solid focal lesions.

Stanford is currently not accepting patients for this trial.For more information, please contact Juergen Willmann, 650-725-1812.

Abstract

Use of robotic surgery has increased in urological practice over the last decade. However, the use, outcomes, and costs of robotic nephrectomy are unknown.To examine the trend in use of robotic-assisted operations for radical nephrectomy in the United States and to compare the perioperative outcomes and costs with laparoscopic radical nephrectomy.This retrospective cohort study used the Premier Healthcare database to evaluate outcomes of patients who had undergone robotic-assisted or laparoscopic radical nephrectomy for renal mass at 416 US hospitals between January 2003 and September 2015. Multivariable regression modeling was used to assess outcomes.Robotic-assisted vs laparoscopic radical nephrectomy.The primary outcome of the study was the trend in use of robotic-assisted radical nephrectomy. The secondary outcomes were perioperative complications, based on the Clavien classification system, and defined as any complication (Clavien grades 1-5) or major complications (Clavien grades 3-5, for which grade 5 results in death); resource use (operating time, blood transfusion, length of hospital stay); and direct hospital cost.Among 23 753 patients included in the study (mean age, 61.4 years; men, 13 792 [58.1%]), 18 573 underwent laparoscopic radical nephrectomy and 5180 underwent robotic-assisted radical nephrectomy. Use of robotic-assisted surgery increased from 1.5% (39 of 2676 radical nephrectomy procedures in 2003) to 27.0% (862 of 3194 radical nephrectomy procedures) in 2015 (P for trend 4 hours) for patients undergoing the robotic-assisted procedure was higher than for patients receiving the laparoscopic procedure in the adjusted analysis (46.3% vs 25.8%; risk difference, 20.5%; 95% CI, 14.2% to 26.8%). Robotic-assisted radical nephrectomy was associated with higher mean 90-day direct hospital costs ($19 530 vs $16 851; difference, $2678; 95% CI, $838 to $4519), mainly accounted for operating room ($7217 vs $5378; difference, $1839; 95% CI, $1050 to $2628) and supply costs ($4876 vs $3891; difference, $985; 95% CI, $473 to $1498).Among patients undergoing radical nephrectomy for renal mass between 2003 and 2015, the use of robotic-assisted surgery increased substantially. The use of robotic-assistance was not associated with increased risk of any or major complications but was associated with prolonged operating time and higher hospital costs compared with laparoscopic surgery.

Abstract

Unidentified distal crossovers, delayed distal crossovers, and impending lateral extrusion are complications of penile prosthesis implant insertion but are not as common as prosthesis infection or mechanical failure.To evaluate results of a surgical technique, the distal corporal anchoring stitch, that addresses fixation of the penile prosthesis in patients with these complications.A lateral sub-coronal incision is used on the side where the crossover or laterally extruding cylinder should be positioned. Dissection is carried through the Buck fascia, followed by a transverse incision of the tunica albuginea, where the distal aspect of the affected cylinder is delivered. A 4-0 PDS suture is threaded through the distal cylinder ring of the implant. A new, properly positioned intracorporal channel is created and the suture is passed through the distal end of the channel. Once the suture is through the glans and the cylinder is in the correct position, a small cruciate incision is made on the glans at the location of the anchor stitch. The suture is tied with the knot buried in the glans tissue.Fifty-three patients underwent treatment of their distal penile implant crossover with a distal corporoplasty using this method and their anatomic and functional outcomes and overall satisfaction were evaluated.This technique ensured that the cylinder remained in the newly created, appropriately positioned channel. No patients developed infections, wound-healing defect, glandular hypoesthesia, anesthesia, or altered sensation or pain in the glans related to the suture and only two reported recurrence of a lateral herniation that did not require further treatment.Distal fixation of the penile prosthesis is a useful surgical adjunct to treating patients with prosthetic lateral extrusions or crossovers that can be applied in almost all cases.Considering these rare complications, our experience is based on a relatively large number of patients and showed a low incidence of complications and a high satisfaction rate. The main limitation of this study is the retrospective nature of the data and the series included patients from two high-volume surgeons that might not be generalizable to all practices.The distal corporal anchoring stitch is safe and effective in securing distal fixation of the extruding inflatable penile prosthesis. Antonini G, Busetto GM, Del Giudice F, et al. Distal Corporal Anchoring Stitch: A Technique to Address Distal Corporal Crossovers and Impending Lateral Extrusions of a Penile Prosthesis. J Sex Med 2017;14:767-773.

Abstract

Little is known about the impact of surgeon volume on the success of the robot-assisted partial nephrectomy (RAPN). The objective of this study was to compare the perioperative outcomes and cost related to RAPN by annual surgeon volumes.Using the Premier Hospital Database, we retrospectively analyzed 39,773 patients who underwent RAPN between 2003 and 2015 in the United States. Surgeons for each index case were grouped into quintiles for each respective year. Outcomes were 90-day postoperative complications, operating room time (ORT), blood transfusion, length of stay, and direct hospital costs. Logistic regression and generalized linear models were used to identify factors predicting complications and cost.After accounting for patient and hospital demographics, high- and very high-volume surgeons had 40% and 42% decreased odds of having major complications (p = 0.045 and p = 0.027, respectively). Surgeons with higher volumes were associated with fewer odds of prolonged ORT (0.68 for low, 0.72 for intermediate, 0.56 for high, 0.44 for very high volume, all p

Abstract

To examine trends in the number of cases of primary vesicoureteral reflux managed by ureteral reimplantation nationally over the last decade. Substantial changes have occurred in management of vesicoureteral reflux (VUR) over time, but trends in use of ureteral reimplantation have yet to be investigated on a national scale with annualized data.Using the Premier Healthcare Database, we extracted hospital discharge data for pediatric patients (age ≤ 18 years) with a procedure code for ureteroneocystostomy (International Classification of Diseases, Ninth Revision, 56.74) between January 1, 2003 and December 31, 2013. We excluded patients with secondary VUR. The presence of a temporal trend in reimplantation was examined via regression using generalized estimating equations.In 4301 cases of primary VUR (23,602 weighted), there was a substantial decrease in the number of reimplantations performed, with an estimated decline in the rate of 0.239 cases per attending per year (P = .006). Average patient age declined 1.2 months in each year (P

Abstract

The purpose of this study was to evaluate the impact of circulating tumor cells (CTCs) as a prognostic marker in patients with high-risk non-muscle-invasive bladder cancer (NMIBC) and assess the efficacy and reliability of 2 different CTC isolation methods.Globally, 155 patients with a pathologically confirmed diagnosis of high-risk NMIBC were included (pT1G3 with or without carcinoma in situ) and underwent transurethral resection of bladder tumor (TURB) after a blood withdrawal for CTC evaluation. A total of 101 patients (Group A) had their samples analyzed with the CellSearch automated system, and 54 (Group B) had their samples analyzed with the CELLection Dynabeads manual system.Patients were followed for 28 months, and during this interval, there were a total of 65 (41.9%) recurrences, 27 (17.4%) disease progressions, and 9 (5.8%) lymph node and/or bone metastasis. In our CTC analysis, there were 20 (19.8%) positive patients in Group A and 24 in Group B (44.4%). In our analysis, we found a strong correlation between CTC presence and time to first recurrence; in Group A, we observed an incidence of recurrence in 75% of CTC-positive patients and in Group B of 83% of CTC-positive patients. The time to progression was also strongly correlated with CTCs: 65% and 29%, respectively, of those patients who progressed in those with CTCs in Group A and B.The study demonstrates the potential role of CTCs as a prognostic marker for risk stratification in patients with NMIBC, to predict both recurrence and progression.

Abstract

The comparative effectiveness of partial nephrectomy versus radical nephrectomy to preserve kidney function has not been well established. We determined the risk of clinically significant (stage 4 and higher) CKD after radical or partial nephrectomy among veterans treated for kidney cancer in the Veterans Health Administration (2001-2013). Among patients with preoperative eGFR≥30 ml/min per 1.73 m(2), the incidence of CKD stage 4 or higher after radical (n=9759) or partial nephrectomy (n=4370) was 7.9% overall. The median time to stage 4 or higher CKD after surgery was 5 months, after which few patients progressed. In propensity score-matched cohorts, partial nephrectomy associated with a significantly lower relative risk of incident CKD stage 4 or higher (hazard ratio, 0.34; 95% confidence interval [95% CI], 0.26 to 0.43, versus radical nephrectomy). In a parallel analysis of patients with normal or near-normal preoperative kidney function (eGFR≥60 ml/min per 1.73 m(2)), partial nephrectomy was also associated with a significantly lower relative risk of incident CKD stage 3b or higher (hazard ratio, 0.15; 95% CI, 0.11 to 0.19, versus radical nephrectomy) in propensity score-matched cohorts. Competing risk regression models produced consistent results. Finally, patients treated with a partial nephrectomy had reduced risk of mortality (hazard ratio, 0.55; 95% CI, 0.49 to 0.62). In conclusion, compared with radical nephrectomy, partial nephrectomy was associated with a marked reduction in the incidence of clinically significant CKD and with enhanced survival. Postoperative decline in kidney function occurred mainly in the first year after surgery and appeared stable over time.

Abstract

Urological surgeries have contributed to the increasing prevalence of minimally invasive robotic procedures. Although factors influencing the adoption of robot-assisted radical prostatectomy have previously been identified, the explanation for the rapid rise in robotic partial nephrectomies remains unknown. Using a retrospective population-based sample, we attempt to determine hospital and surgeon-specific factors influencing a surgeon's decision to utilize robotic assistance for partial nephrectomies.A nationally representative weighted sample of all men who underwent a partial nephrectomy in the United States between 2003 and 2014 was identified within the Premier Hospital Database. Hospital, surgeon, and patient characteristics for each operation were analyzed. Descriptive statistics and a multivariate regression model stratified according to the Law of Diffusion of Innovation were performed.A weighted sample of 14,890 nephrectomies was included in the study. Patient demographics were similar between the two groups. The adoption of robotic technology followed the Law of Diffusion of Innovation with the percentage of partial nephrectomies with robotic assistance increasing yearly, reaching 64.1% by 2013. Surgical volume was a significant factor driving the use of robotic assistance, with high volume surgeons (>5 partial nephrectomies/year) performing 23.2% more robotic partial nephrectomies per year than their low volume colleagues (

Abstract

Partial nephrectomy (PN) remains underutilized within the United States and few reports have attempted to explain this trend. The aim of this study is to evaluate the nationwide incidence of unsuccessful PN and factors that predict its occurrence.Using the Premier Healthcare Database, we retrospectively analyzed a weighted sample of 66,432 patients undergoing curative surgery for renal mass between 2003 and 2015. PN intent was denoted by presence of insurance claims for the administration of mannitol. Unsuccessful PN was defined as an event in which patients were administered mannitol but received radical nephrectomy. A multivariate logistic regression model was generated to identify factors predicting unsuccessful PN.Overall rates of unsuccessful PN declined from 33.5% to 14.5% since 2003. Conversion to radical nephrectomy occurred most frequently during laparoscopic (34.7%) and least frequently during robotic approach (13.6%). There was significant difference in the rate of unsuccessful PN between very high and very low volume surgeons (open: 39.4% vs. 13.3%, laparoscopic: 51.2% vs. 32.2%, and robot assisted: 27.1% vs. 9.4%, all P<0.001). After adjustment for patient- and hospital-related factors, surgical approach (laparoscopic vs. open, odds ratio = 1.74, 95% CI: 1.31-2.30, P<0.001) and annual surgeon volume (very high vs. very low, odds ratio = 0.27, 95% CI: 0.21-0.34 P<0.001) were associated with unsuccessful PN.Although the rate of unsuccessful PN appears to be declining, it still remains common for low volume surgeons and with the laparoscopic surgical approach. Further evaluation of its effect on health care outcomes is necessary.

Abstract

Limited literature exists on the association between androgen deprivation therapy (ADT) for prostate cancer (PCa) and subsequent dementia and the study conclusions are in conflicts with one another. We searched several cohort databases from 1960 to 2017 for observational or prospective studies that reported on an association between ADT for PCa and subsequent dementia. A meta-analysis was performed to cumulatively determine the association between ADT and dementia including Alzheimer's disease using an incidence rate ratio (IRR), crude hazard ratio (HR), and adjusted HR. Seven studies were eligible for the meta-analysis, with the inclusion of a total of 90, 543 prostate cancer patients. The pooled overall IRR, crude HR, and adjusted HR were 1.78 [95% confidence interval (CI): 1.51-2.10)], 1.80 (95% CI: 1.05-3.10), and 1.59 (95% CI: 1.16-2.18), respectively. A meta-regression analysis showed that the crude HR was affected by both follow -up duration and lag time in the univariate model (p = < 0.001). However, IRR and adjusted HR were not affected by these moderators. The overall outcomes of IRR, crude HR, and adjusted HR were found to be balanced in the sensitivity analysis. A positive association was demonstrated between ADT and the subsequent incidence of dementia in this meta-analysis. Methodological difference including follow-up duration and the time lag could be related with the discrepancies.

Abstract

Data on the utilization of open, laparoscopic and robotic adrenalectomy on a national level is limited.Data on patients who underwent open, laparoscopic, or robotic adrenalectomy for benign or malignant disease in the US from 2003-2013 were extracted using ICD-9 codes from the Premier Hospital Database. Surgeon specialty, patient demographics, hospital characteristics, and complications were compared. Data were analyzed using univariate and multivariable logistic regression analyses.A total of 8,831 adrenalectomies were performed for benign and malignant tumors. There was no significant difference in rate of adrenalectomy with regards to comorbidities, insurance status, or hospital characteristics. Non-urologists performed adrenalectomy more often for both benign (57% versus 43%; p = 0.011) and malignant disease (66% versus 34%; p = 0.011). Across all indications, non-urologists performed open surgery most often followed by laparoscopic and robotic approaches (56.3% versus 37.4% versus 6.4%, respectively), compared to urologists (48.8% versus 38.4% versus 12.9%, respectively). Overall, urologists were more likely to use laparoscopic or robotic approaches (p = 0.001). There was no difference in complication rates or operative times between surgical specialties or by surgeon/hospital case volume. On multivariable regression analysis, the best predictor of major complication was a Charlson Comorbidity Index (CCI) ≥ 2 (OR 3.9, 95%CI 2.1-7.1; p = < 0.001). Compared to open surgery, laparoscopy had significantly reduced odds of major complication (OR 0.6, 95%CI 0.3-0.9; p = 0.03). Patients undergoing robotic procedures had the shortest length of stay.In this retrospective study, adrenalectomy was more commonly performed by non-urologists via an open approach. Patients with CCI ≥ 2 were more likely to have postoperative complications while surgeon volume, hospital volume, and surgical approach did not influence complication rates.

Abstract

Radical cystectomy (RC) for muscle-invasive bladder cancer (BCa) has potential for serious complications, prolonged length of stay and readmissions-all of which may increase costs. Although variations in outcomes are well described, less is known about determinants driving variation in costs.To assess surgeon- and hospital-level variations in costs and predictors of high- and low-cost RC.Cohort study of 23 173 patients who underwent RC for BCa in 208 hospitals in the USA from 2003 to 2015 in the Premier Healthcare Database.Ninety-day direct hospital costs; multilevel hierarchal linear models were constructed to evaluate contributions of each variable to costs.Mean 90-d direct hospital costs per RC was $39 651 (standard deviation $34 427), of which index hospitalization accounted for 87.8% ($34 803) and postdischarge readmission(s) accounted for 12.2% ($4847). Postoperative complications contributed most to cost variations (84.5%), followed by patient (49.8%; eg, Charlson Comorbidity Index [CCI], 40.5%), surgical (33.2%; eg, year of surgery [25.0%]), and hospital characteristics (8.0%). Patients who suffered minor complications (odds ratio [OR] 2.63, 95% confidence interval [CI]: 2.03-3.40), nonfatal major complications (OR 12.7, 95% CI: 9.63-16.8), and mortality (OR 13.5, 95% CI: 9.35-19.4, all p<0.001) were significantly associated with high costs. As for low-cost surgery, sicker patients (CCI=2: OR 0.41, 95% CI: 0.29-0.59; CCI=1: OR 0.58, 95% CI: 0.46-0.75, both p<0.001), those who underwent continent diversion (vs incontinent diversion: OR 0.29, 95% CI: 0.16-0.53, p<0.001), and earlier period of surgery were inversely associated with low costs.This study provides insight into the determinants of costs for RC. Postoperative morbidity, patient comorbidities, and year of surgery contributed most to observed variations in costs, while other hospital- and surgical-related characteristics such as volume, use of robot assistance, and type of urinary diversion contribute less to outlier costs.Efforts to address high surgical cost must be tailored to specific determinants of high and low costs for each operation. In contrast to robot-assisted radical prostatectomy where surgeon factors predominate, high costs in radical cystectomy were primarily determined by postoperative complication and patient comorbidities.

Abstract

To examine trends in utilization of open, laparoscopic and robot-assisted surgical approaches for treatment of patients with chronic kidney disease (CKD) undergoing partial nephrectomy (PN) within the USA.We analyzed a weighted sample of 112,117 patients from the Premier administrative dataset who underwent PN for renal mass between 2003 and 2015. Proportions of surgical approach utilization were evaluated by CKD status and further stratified by surgery year and surgeon volume. A multivariate logistic regression model was created to predict receipt of minimally invasive PN.Seven thousand five hundred and sixty-five (6.7%) patients with CKD were identified. The proportion of CKD patients receiving open PN decreased from 72.4% in 2003-2007 to 36.1% in 2012-2015 (p

Abstract

We sought to compare complications and direct costs for open ureteral reimplantation (OUR) versus robot-assisted laparoscopic ureteral reimplantation (RALUR) in a sample of hospitals performing both procedures. Anecdotal reports suggest that use of RALUR is increasing, but little is known of the outcomes and costs nationwide.The aim was to determine the costs and 90-day complications (of any Clavien grade) in a nationwide cohort of pediatric patients undergoing OUR or RALUR.Using the Premier Hospital Database we identified pediatric patients (age

Abstract

More than a decade since its inception, the benefits and cost efficiency of robot-assisted radical prostatectomy (RARP) continue to elicit controversy.To compare outcomes and costs between RARP and open RP (ORP).A cohort study of 629 593 men who underwent RP for localized prostate cancer at 449 hospitals in the USA from 2003 to 2013, using the Premier Hospital Database.RARP was ascertained through a review of the hospital charge description master for robotic supplies.Outcomes were 90-d postoperative complications (Clavien), blood product transfusions, operating room time (ORT), length of stay (LOS), and direct hospital costs. Propensity-weighted regression analyses accounting for clustering by hospitals and survey weighting ensured nationally representative estimates.RARP utilization rapidly increased from 1.8% in 2003 to 85% in 2013 (p<0.001). RARP patients (n=311 135) were less likely to experience any complications (odds ratio [OR] 0.68, p<0.001) or prolonged LOS (OR 0.28, p<0.001), or to receive blood products (OR 0.33, p=0.002) compared to ORP patients (n=318 458). The adjusted mean ORT was 131min longer for RARP (p=0.002). The 90-d direct hospital costs were higher for RARP (+$4528, p<0.001), primarily attributed to operating room and supplies costs. Costs were no longer signficantly different between ORP and RARP among the highest-volume surgeons (≥104 cases/yr; +$1990, p=0.40) and highest-volume hospitals (≥318 cases/yr; +$1225, p=0.39). Limitations include the lack of oncologic characteristics and the retrospective nature of the study.Our contemporary analysis reveals that RARP confers a perioperative morbidity advantage at higher cost. In the absence of large randomized trials because of the widespread adoption of RARP, this retrospective study represents the best available evidence for the morbidity and cost profile of RARP versus ORP.In this large study of men with prostate cancer who underwent either open or robotic radical prostatectomy, we found that robotic surgery has a better morbidity profile but costs more.

Abstract

To better define the shift in the management of renal trauma throughout the United States, with a population-based assessment of community hospital practice patterns. To investigate how hospital, patient, and injury-specific factors influence management strategy by both urologists and nonurologists.Using the Premier Hospital database, we performed a retrospective study of all patients with renal trauma between 2003 and 2013. We identified patients using International Classification of Diseases, Ninth Revision diagnosis codes (866.0x, 866.1x), determined management strategy by International Classification of Diseases, Ninth Revision procedure codes, and dichotomized grouping by surgeon specialty. We stratified hospitals by annual renal trauma volume categorized a priori into low, <10 cases per year; intermediate, 10-20 cases per year; and high, >20 cases per year. We performed descriptive statistics and univariate and multivariate regression analyses adjusting for survey weighting and for patient, hospital, and injury-specific characteristics.Our study cohort included a weighted sample size of 21,531 patients. Higher renal trauma hospitals (12.6%) were significantly less likely than low (26.4%) and intermediate (31.3%) volume hospitals to undergo surgical intervention for renal trauma on adjusted models. There was a statistically significant increase in nonoperative management from 65.2% in 2003 to 81.8% in 2013.National rates of surgical intervention for renal trauma are significantly higher than those frequently quoted by the literature, especially among low- and intermediate-volume renal trauma hospitals. Although operative rates are decreasing, further consideration may need to be given to centralization of care in higher-volume teaching hospitals to improve renal salvage.

Abstract

We assessed surgeon and hospital level variation in robot-assisted radical prostatectomy costs and predictors of high and low cost surgery.The study population consisted of a weighted sample of 291,015 men who underwent robot-assisted radical prostatectomy for prostate cancer by 667 surgeons at 197 U.S. hospitals from 2003 to 2013. We evaluated 90-day direct hospital costs (2014 USD) in the Premier Hospital Database. High costs per robot-assisted radical prostatectomy were those above the 90th percentile and low costs were those below the 10th percentile.Mean hospital cost per robot-assisted radical prostatectomy was $11,878 (95% CI $11,804-$11,952). Mean cost was $2,837 (95% CI $2,805-$2,869) in the low cost group vs $25,906 (95% CI $24,702-$25,490) in the high cost group. Nearly a third of the variation in robot-assisted radical prostatectomy cost was attributable to hospital characteristics and more than a fifth was attributable to surgeon characteristics (R-squared 30.43% and 21.25%, respectively). High volume surgeons and hospitals (90th percentile or greater) had decreased odds of high cost surgery (surgeons: OR 0.24, 95% CI 0.11-0.54; hospitals: OR 0.105, 95% CI 0.02-0.46). The performance of robot-assisted radical prostatectomy at a high volume hospital was associated with increased odds of low cost robot-assisted radical prostatectomy (OR 839, 95% CI 122-greater than 999).This study provides insight into the role of surgeons and hospitals in robot-assisted radical prostatectomy costs. Given the substantial variability, identifying and remedying the root cause of outlier costs may yield substantial benefits.

Abstract

To assess whether patient factors, such as age and preoperative kidney function, were associated with receipt of partial nephrectomy in a national integrated healthcare system.We identified patients treated with a radical or partial nephrectomy from 2002 to 2014 in the Veterans Health Administration. We examined associations among patient age, sex, race or ethnicity, multimorbidity, baseline kidney function, tumor characteristics, and receipt of partial nephrectomy. We estimated the odds of receiving a partial nephrectomy and assessed interactions between covariates and the year of surgery to explore whether patient factors associated with partial nephrectomy changed over time.In our cohort of 14,186 patients, 4508 (31.2%) received a partial nephrectomy. Use of partial nephrectomy increased from 17% in 2002 to 32% in 2008 and to 38% in 2014. Patient race or ethnicity, age, tumor stage, and year of surgery were independently associated with receipt of partial nephrectomy. Black veterans had significantly increased odds of receipt of partial nephrectomy, whereas older patients had significantly reduced odds. Partial nephrectomy utilization increased for all groups over time, but older patients and patients with worse baseline kidney function showed the least increase in odds of partial nephrectomy.Although the utilization of partial nephrectomy increased for all groups, the greatest increase occurred in the youngest patients and those with the highest baseline kidney function. These trends warrant further investigation to ensure that patients at the highest risk of impaired kidney function are considered for partial nephrectomy whenever possible.

Abstract

A better understanding of overall survival among patients with clinically localized prostate cancer (PCa) in the US Veterans Health Administration (VHA) is critical to inform PCa treatment decisions, especially in light of data from the Prostate Intervention Versus Observation Trial (PIVOT). We sought to describe patterns of survival for all patients with clinically localized PCa treated by the VHA. We created an analytic cohort of 35 954 patients with clinically localized PCa diagnosed from 1995 to 2001, approximating the PIVOT inclusion criteria (age of diagnosis ≤75 yr and clinical stage T2 or lower). Mean patient age was 65.9 yr, and median follow-up was 161 mo. Overall, 22.5% of patients were treated with surgery, 16.6% were treated with radiotherapy, and 23.1% were treated with androgen deprivation. Median survival of the entire cohort was 14 yr (25th, 75th percentiles, range: 7.9-20 yr). Among patients who received treatment with curative intent, median survival was 17.9 yr following surgery and 12.9 yr following radiotherapy. One-third of patients died within 10 yr of diagnosis compared with nearly half of the participants in PIVOT. This finding sounds a note of caution when generalizing the mortality data from PIVOT to VHA patients and those in the community.More than one-third of patients diagnosed with clinically localized prostate cancer treated through the US Veterans Health Administration from 1995 to 2001 died within 10 yr of their diagnosis. Caution should be used when generalizing the estimates of competing mortality data from PIVOT.

Abstract

To perform a population-based study to evaluate contemporary utilization trends, morbidity and costs associated with nephroureterectomies (NU). Contemporary data for NU are largely derived from single academic institution series describing the experience of high-volume surgeons. It is unclear if the same favorable results occur on a national level.Using the Premier Hospital Database, we captured patients undergoing a NU with diagnoses of renal pelvis or ureteral neoplasms from 2004 to 2013. We fitted regression models, adjusting for clustering by hospitals and survey weighting to evaluate 90-day postoperative complications, operating-room-time (OT), prolonged length-of-stay (pLOS) and direct hospital costs among open, laparoscopic (LNU) and robotic (RNU) approaches.After applying sampling and propensity weights we derived a final study cohort of 17,254 ONU, 13,317 LNU and 3,774 RNU for UTUC in the US between 2004 and 2013. During that period, minimally invasive NU (miNU) increased from 36%-to-54% while the total number of NUs decreased by nearly 20%. No differences were noted in perioperative outcomes between three surgical approaches, including when the analysis was restricted to highest-volume hospitals and highest-volume surgeons. OT was longer for LNU and RNU (p<0.001), where the pLOS rates were decreased for LNU and RNU (p <0.001). Adjusted 90-day median direct-hospital-costs were higher for LNU and RNU (p<0.001), which disappear when adjusting for the highest-volume groups except in RNUs performed by high-volume surgeons.During this contemporary 10-year study, miNU is replacing open surgery for UTUC with a recent surge in RNU, along with a concurrent reduction in total NUs performed. Despite not being associated with a clinically significant improvement in perioperative outcomes, the costs for miNU were consistently higher. However, higher hospital volumes suggest a potential cost containment strategy when performing miNUs. This article is protected by copyright. All rights reserved.

Abstract

Prostate cancer is an extremely prevalent cause of morbidity and mortality among American men. Several different treatments exist, but differences in utilization between these treatments are not well understood.We performed an observational study using administrative datasets linked to hospital survey data, which included non-metastatic prostate cancer patients receiving robot-assisted radical prostatectomy (RARP) or open radical prostatectomy (ORP) in California, Florida, or New York from 2009-2011. We developed two hierarchical regression models with fixed effect accounting for hospital clustering and physician clustering to determine factors associated with utilization of RARP versus ORP at hospitals offering robotic surgery.A total of 36,694 patients were identified, with 77.13% receiving RARP and 22.87% receiving ORP. African American patients had lower RARP rates than White patients (OR = 0.80, p < 0.001). Patients using Medicare (OR = 0.91, p = 0.028), Medicaid (OR = 0.68, p < 0.001), or self-pay (OR = 0.72, p = 0.046) had lower RARP rates than patients using private insurance. Patients in Florida had lower RARP rates than patients in California (OR = 0.48, p = 0.010). Patients treated at teaching hospitals had lower RARP rates than patients treated at non-teaching hospitals (OR = 0.50, p = 0.006). The average cost of RARP was $13,614.83, and the average cost of ORP was $12,167.44 (p < 0.001).This population based study suggests that both patient and hospital characteristics are associated with utilization of RARP versus ORP in hospitals where robotic surgery is offered.

Abstract

Targeted therapies (TTs) have revolutionized metastatic renal cell carcinoma (mRCC) treatment in the past decade, largely replacing immunotherapy including high-dose interleukin-2 (HD IL-2) therapy. We evaluated trends in HD IL-2 use for mRCC in the TT era.Our cohort comprised a weighted estimate of all patients undergoing HD IL-2 treatment for mRCC from 2004 to 2012 using the Premier Hospital Database. We assessed temporal trends in HD IL-2 use including patient, disease, and hospital characteristics stratified by era (pre-TT uptake: 2004-2006, uptake: 2007-2009, and post-TT uptake: 2010-2012) and fitted multivariable regression models to identify predictors of treatment toxicity and tolerability.An estimated 2,351 patients received HD IL-2 therapy for mRCC in the United States from 2004 to 2012. The use decreased from 2004 to 2008. HD IL-2 therapy became increasingly centralized in teaching hospitals (24% of treatments in 2004 and 89.5% in 2012). Most patients who received HD IL-2 therapy were men, white, younger than 60 years, had lung metastases, and were otherwise healthy. Vasopressors, intensive care unit admission, and hemodialysis were necessary in 53.4%, 33.0%, and 7.1%, respectively. Factors associated with toxicities in multivariable analyses included being unmarried, male sex, and multiple metastatic sites. African Americans and patients with single-site metastases were less likely to receive multiple treatment cycles.HD IL-2 therapy is used infrequently for mRCC in the United States, and its application has diminished with the uptake of TT. Patients are being increasingly treated in teaching hospitals, suggesting a centralization of care and possible barriers to access. A recent slight increase in HD IL-2 therapy use likely reflects recognition of the inability of TT to effect a complete response.

Abstract

To describe the surgeon characteristics associated with RARP adoption and determine the possible impact of this adoption on practice patterns and cost.A retrospective cohort study with a weighted sample size of 489,369 men who underwent non-RARP (i.e., open or laparoscopic radical prostatectomy [RP]) or RARP in the United States from 2003 to 2010 was performed. We evaluated predictors for RARP adoption, defined as performing >50% of annual RP with the robotic approach. Additionally, we identified the resulting changes in prostate cancer surgery practice patterns and expenditures.From 2003 to 2010, RARP adoption increased from 0.7% to 42% of surgeons performing RP. High-volume surgeons, defined as performing >24 RP annually, had statically significantly higher odds of adopting RARP throughout the study period. From 2005 to 2007, adoption was more common among surgeons at teaching (OR: 2.4; 95% CI: 1.7-3.4), intermediate- (200-399 beds; OR: 5.96; 95% CI: 1.3-26.5) and large-sized hospitals (≥400 beds; OR: 6.1; 95% CI: 1.4-25.8); after 2007, adoption was more common among surgeons at urban hospitals (OR: 3.3; 95% CI: 1.7 to 6.4). RARP adoption was generally associated with increased RP volume, greatest for high-volume surgeons and least for low-volume surgeons (<5 RP annually). The annual number of surgeons performing RP decreased from approximately 10,000 to 8,200, with the proportion of cases performed by high-volume surgeons increasing from 10% to 45%. RARP was more costly, disproportionally contributing to the 40% increase in annual prostate cancer surgery expenditures. RARP costs generally decreased plateauing at over $10,000 while non-RARP costs increased to nearly $9,000 by the end of the study.There was widespread RARP adoption in the United States between 2003 and 2010, particularly among high-volume surgeons. The diffusion of RARP was associated with a centralization of care and an increased economic burden for prostate cancer surgery.

Abstract

To perform a population-based study that evaluates contemporary racial disparities in the morbidity profile of patients undergoing radical nephrectomy in the United States.Using the Premier hospital database (Premier Inc, Charlotte, NC), which collects data from over 600 nonfederal hospitals throughout the United States, we identified patients undergoing a total nephrectomy as their primary procedure and also had a concurrent diagnosis of a kidney mass or cancer from 2003 to 2010. The primary outcome was 90-day major complication rates, based on the Clavien classification system. Multivariate logistic regression models were performed, adjusting for clustering by hospitals and survey weighting to ensure nationally representative estimates.The study population included 25,517 patients translating into a weighted sample of 185,135 radical nephrectomies. In a multivariate model including patient, hospital, and surgical characteristics, blacks were more commonly associated with a major complication (odds ratio, 2.1; P

Abstract

To evaluate the relationship between surgeon volume of radical cystectomy (RC) and postoperative morbidity as well as the economic burden of bladder cancer in the United States.We captured all patients who underwent a RC (ICD-9 code 57.71) from 2003 to 2010, using a nationwide hospital discharge database. Patient, hospital, and surgical characteristics were evaluated. Annual volume of RC for surgeons was divided into quintiles. Multivariable regression models were developed adjusting for clustering and survey weighting to evaluate the outcomes including 90-day major complications (Clavien 3-5) and direct patient costs. We adjusted for clustering and weighting to achieve a nationally representative analysis.The weighted cohort included 49,792 RC patients with an overall 90-day major complication rate of 16.2%. Compared to surgeons performing one RC annually, surgeons performing ≥7 RC each year had a 45% decreased odds of major complications (OR: 0.55, p<0.001) and a reduction in costs by $1690 (p=0.02). Results were consistent when we analyzed surgeon volume as a continuous variable and when we examined the highest volume surgeons (≥28 cases annually), which found a marked decreased odds of major complications compared to the lowest volume surgeons (OR: 0.45, 95% CI: 0.31-0.67, p<0.0001). Compared to patients who did not have any complications, those who suffered a major complication had significantly higher 90-day median direct hospital costs ($43965 vs. $24341, p<0.0001).We demonstrate an inverse relationship between surgeon volume and the development of postoperative 90-day major complication rates as well as direct hospital costs. Centralization of RC to higher volume surgeons may reduce the development of postoperative major complications thereby decreasing the burden of bladder cancer on the health care system.

The Contemporary Incidence and Sequelae of Rhabdomyolysis Following Extirpative Renal Surgery: A Population-Based Analysis.The Journal of urology2015

Abstract

To evaluate the contemporary incidence and consequences of postoperative rhabdomyolysis (PRM) following extirpative renal surgery (ERS).We conducted a population-based, retrospective cohort study of patients who underwent ERS with a diagnosis of a renal mass or renal cell carcinoma in the United States between 2004 and 2013. Regression analysis was performed to evaluate 90-day mortality (Clavien grade 5), non-fatal major complications (Clavien grade 3-4), readmission rates, direct costs and length of stay (LOS).The final weighted cohort included 310,880 open, 174,283 laparoscopic, and 69,880 robotic ERS during the 10-year study period, with 745 (0.001%) experiencing PRM. Presence of PRM led to a significantly higher incidence of 90-day non-fatal major complications (34.7% vs. 7.3%, p<0.05) and higher 90-day mortality (4.4% vs. 1.02%, p<0.05). LOS was twice as long for patients with PRM (incidence risk ratio: 1.83, 95% CI: 1.56-2.15, p<0.001). Robotic approach was associated with a higher likelihood for PRM (vs. laparoscopic approach, odds ratio: 2.43, p<0.05). Adjusted 90-day median direct hospital costs were USD 7515 higher for patients with PRM (p<0.001). Our model revealed that the combination of obesity and prolonged surgery (>5 hours) was associated with a higher likelihood of developing PRM.Our study confirms that PRM is an uncommon complication among patients undergoing ERS but has a potentially detrimental impact on surgical morbidity, mortality and costs. Male gender, comorbidities as well as obesity, prolonged surgery (>5 hours), and a robotic approach appear to place patients at a higher risk for PRM.

Abstract

Based on revisions of Gleason scoring in 2005, it has been reported that nodal metastases at radical prostatectomy in Gleason 3 + 3 = 6 (GS6) prostate cancer are extremely rare, and that GS6 cancers with nodal metastases are invariably upgraded upon review by academic urological pathologists. We analysed the prevalence and determinants of nodal metastases in a national sample of patients with GS6 cancer.We utilised the SEER database to identify patients diagnosed with GS6 prostate cancer during 2004-2010 who had radical prostatectomy and ≥1 lymph node(s) examined. We calculated the prevalence of nodal metastases and constructed a multivariable logistic regression model to identify factors associated with nodal metastases.Among 21,960 patients, the prevalence of nodal metastases was 0.48%. Older age, preoperative PSA >10 ng/mL, and advanced stage were positively associated with nodal metastases.Lymph node metastases in GS6 cancer are more prevalent in a nationwide population compared to academic centres. Revised guidelines for Gleason scoring have made GS6 cancer a more homogeneously indolent disease, which may be relevant in the era of active surveillance. We submit that lymph node metastases in GS6 cancer be used as a proxy for adherence to the 2005 ISUP consensus on Gleason grading.

Abstract

We sought to examine the trends in perioperative outcomes of kidney cancer surgery stratified by type (radical nephrectomy [RN] vs. partial nephrectomy [PN]) and approach (open vs. minimally invasive).We queried the National Surgical Quality Improvement Program database to identify kidney cancer operations performed from 2005 to 2011. We examined 30-day perioperative outcomes including operative time, transfusion rate, length of stay, major morbidity (cardiovascular, pulmonary, renal, and infectious), and mortality.A total of 2,902 PN and 5,459 RN cases were identified. The use of PN increased over time, accounting for 39% of all nephrectomies in 2011. Minimally invasive approaches also increased over time for both RN and PN. Open surgery was associated with increased length of stay, receipt of transfusion, major complications, and perioperative mortality. Resident involvement and open approach were independent predictors of major complications for both PN and RN. Additionally, the presence of a medical comorbidity was also a risk factor for complications after RN. The overall complication rates decreased for all approaches over the study period.Minimally invasive approaches to kidney cancer renal surgery have increased with favorable outcomes. The safety of open and minimally invasive PN improved significantly over the study period. Although pathologic features cannot be determined from this data set, these data show that complications from renal surgical procedures are decreasing in an era of increasing use.

Abstract

Asian-American men with prostate cancer have been reported to present with higher grade and later stage disease than White Americans. However, Asian Americans comprise a heterogeneous population with distinct health outcomes. We compared prostate cancer risk profiles among the diverse racial and ethnic groups in California.We used data from the California Cancer Registry for 90,845 Non-Hispanic White, Non-Hispanic Black, and Asian-American men diagnosed with prostate cancer between 2004 and 2010. Patients were categorized into low, intermediate, or high-risk groups based on clinical stage, Gleason score, and PSA value at diagnosis. Using polytomous logistic regression, we estimated adjusted odds ratios for the association of race/ethnicity and nativity with risk group.In addition to Non-Hispanic Blacks, six Asian-American groups (US-born Chinese, foreign-born Chinese, US-born Japanese, foreign-born Japanese, foreign-born Filipino, and foreign-born Vietnamese) were more likely to have an unfavorable risk profile compared to Non-Hispanic Whites. The odds ratios for high vs. intermediate-risk disease ranged from 1.23 (95% CI, 1.02-1.49) for US-born Japanese to 1.45 (95% CI, 1.31-1.60) for foreign-born Filipinos. These associations appeared to be driven by higher grade and PSA values, rather than advanced clinical stage at diagnosis.In this large, ethnically diverse population-based cohort, we found that Asian-American men were more likely to have unfavorable risk profiles at diagnosis. This association varied by racial/ethnic group and nativity, and was not attributable to later stage at diagnosis, suggesting that Asian men may have biological differences that predispose to the development of more severe disease.

Abstract

The chromophobe subtype of renal cell carcinoma (chRCC) has generally been associated with a better prognosis than the clear cell type; however, debate continues as to absolute prognosis as well as the significance of certain prognostic variables. We investigated the significance of pathologic stage and a recently proposed chromophobe tumor grading (CTG) scheme in predicting chRCC outcomes.All available chRCCs were identified from our surgical pathology archives from 1987-2010. Original slides were reviewed to verify diagnoses and stage, and each case was graded following a novel chromophobe tumor grade system criteria. Disease status was obtained from a clinical outcome database, and cancer specific deaths and recurrences were recorded.Eighty-one cases of chRCC were identified, and 73 had adequate follow-up information available. There were only 3 instances of cancer related recurrence or mortality, which included 1 disease specific mortality and 2 disease recurrences. Pathologic stage and CTG 3 were found to be significantly associated with the recurrences or death from chRCC, but there was no association with CTG 1 and CTG 2.chRCC is associated with a very low rate of cancer specific events (4.1%) even at a tertiary referral center. In our study, pathologic stage and CTG 3, but not CTG 1 or 2, were significantly associated with the development of these events.

Abstract

To examine the patient, tumor, and temporal factors associated with receipt of renal mass biopsy (RMB) in a contemporary nationally representative sample.We queried the Surveillance, Epidemiology, and End Results-Medicare data set for incident cases of renal cell carcinoma diagnosed between 1992 and 2007. We tested for associations among receipt of RMB and patient and tumor characteristics, type of therapy, and procedure type. Temporal trends in receipt of RMB were characterized over the study period.Approximately 1 in 5 (20.7%) patients diagnosed with renal cell carcinoma (n = 24,702) underwent RMB before instituting therapy. There was a steady and modest increase in RMB utilization, with the highest utilization (30%) occurring in the final study year. Of patients who underwent radical (n = 15,666) or partial (n = 2211) nephrectomy, 17% and 20%, respectively, underwent RMB in advance of surgery. Sixty-five percent of patients who underwent ablation (n = 314) underwent RMB before or in conjunction with the procedure. Roughly half of patients (50.4%) treated with systemic therapy alone underwent RMB. Factors independently associated with use of RMB included younger age, black race, Hispanic ethnicity, tumor size <7 cm, and metastatic disease at presentation.At present, most patients who eventually undergo radical or partial nephrectomy do not undergo RMB, whereas most patients who eventually undergo ablation or systemic therapy do. The optimal use of RMB in the evaluation of kidney tumors has yet to be determined.

Abstract

We performed a population based study comparing trends in perioperative outcomes and costs for open, laparoscopic and robotic pediatric pyeloplasty. Specific billing items contributing to cost were also investigated.Using the Perspective database (Premier, Inc., Charlotte, North Carolina), we identified 12,662 pediatric patients who underwent open, laparoscopic and robotic pyeloplasty (ICD-9 55.87) in the United States from 2003 to 2010. Univariate and multivariate statistics were used to evaluate perioperative outcomes, complications and costs for the competing surgical approaches. Propensity weighting was used to minimize selection bias. Sampling weights were used to yield a nationally representative sample.A decrease in open pyeloplasty and an increase in minimally invasive pyeloplasty were observed. All procedures had low complication rates. Compared to open pyeloplasty, laparoscopic and robotic pyeloplasty had longer median operative times (240 minutes, p <0.0001 and 270 minutes, p <0.0001, respectively). There was no difference in median length of stay. Median total cost was lower among patients undergoing open vs robotic pyeloplasty ($7,221 vs $10,780, p <0.001). This cost difference was largely attributable to robotic supply costs.During the study period open pyeloplasty made up a declining majority of cases. Use of laparoscopic pyeloplasty plateaued, while robotic pyeloplasty increased. Operative time was longer for minimally invasive pyeloplasty, while length of stay was equivalent across all procedures. A higher cost associated with robotic pyeloplasty was driven by operating room use and robotic equipment costs, which nullified low room and board cost. This study reflects an adoption period for robotic pyeloplasty. With time, perioperative outcomes and cost may improve.

Abstract

To evaluate the frequency and clinical characteristics of postoperative hemorrhage as a complication of partial nephrectomy.The demographics, physical statistics, tumor size, R.E.N.A.L. nephrometry score, operative method, warm ischemic time, and presence of postoperative hemorrhage and its severity and method of intervention were examined in 300 partial nephrectomy patients in two medical centers (Stanford Medical Center and Kyung Hee University Medical Center) between March 2000 and March 2012.Of the 300 subjects, 13 (4.3%) experienced postoperative hemorrhage severe enough to require intervention more invasive than transfusion (Clavien grade III or higher). Univariate analysis of the bleeding and nonbleeding groups showed that whereas age, ischemic time, tumor size and stage, body mass index, American Society of Anesthesiologists class, and operative method did not differ significantly, the exophyticity (E) score was significantly higher for severe postoperative hemorrhage (p=0.04). However, multivariate analysis showed none of the factors to differ significantly. In most of the cases requiring intervention, selective embolization was sufficient, but in one case explorative laparotomy and nephrectomy were required. Clinical characteristics varied significantly among severe hemorrhage cases, with time of onset ranging from the first to the 30th postoperative day and symptoms presenting in a diverse manner, such as gross hematuria and pleuritic chest pain. Computed tomography and angiographic findings were consistent with either arteriovenous fistula or pseudoaneurysms.Severe hemorrhage after partial nephrectomy is rare. Nonetheless, with the great variability in presenting symptoms and time of onset after surgery, surgeons should exercise great vigilance during the postoperative care of partial nephrectomy patients.

Propensity-Matched Comparison of Morbidity and Costs of Open and Robot-Assisted Radical Cystectomies: A Contemporary Population-Based Analysis in the United States.European urology2014

Abstract

Radical cystectomy (RC) is a morbid procedure associated with high costs. Limited population-based data exist on the complication profile and costs of robot-assisted RC (RARC) compared with open RC (ORC).To evaluate morbidity and cost differences between ORC and RARC.We conducted a population-based, retrospective cohort study of patients who underwent RC at 279 hospitals across the United States between 2004 and 2010.Multivariable logistic and median regression was performed to evaluate 90-d mortality, postoperative complications (Clavien classification), readmission rates, length of stay (LOS), and direct costs. To reduce selection bias, we used propensity weighting with survey weighting to obtain nationally representative estimates.The final weighted cohort included 34 672 ORC and 2101 RARC patients. RARC use increased from 0.6% in 2004 to 12.8% in 2010. Major complication rates (Clavien grade ≥3; 17.0% vs 19.8%, p=0.2) were similar between ORC and RARC (odds ratio [OR]: 1.32; p=0.42). RARC had 46% decreased odds of minor complications (Clavien grade 1-2; OR: 0.54; p=0.03). RARC had $4326 higher adjusted 90-d median direct costs (p=0.004). Although RARC had a significantly shorter LOS (11.8 d vs 10.2 d; p=0.008), no significant differences in room and board costs existed (p=0.20). Supply costs for RARC were significantly higher ($6041 vs $3638; p<0.0001). Morbidity and cost differences were not present among the highest-volume surgeons (≥7 cases per year) and hospitals (≥19 cases per year). Limitations include use of an administrative database and lack of oncologic characteristics.The use of RARC has increased between 2004 and 2010. Compared with ORC, RARC was associated with decreased odds of minor but not major complications and with increased expenditures attributed primarily to higher supply costs. Centralization of ORC and RARC to high-volume providers may minimize these morbidity and cost differences.Using a US population-based cohort, we found that robotic surgery for bladder cancer decreased minor complications, had no impact on major complications and was more costly than open surgery.

Abstract

To identify factors associated with the development of chronic kidney disease (CKD) after nephrectomy and to create a clinical model to predict CKD after nephrectomy for kidney cancer for clinical use.We identified 144 patients who had normal renal function (eGFR > 60) prior to undergoing nephrectomy for kidney cancer. Selected cases occurred between 2007 and 2010 and had at least 30 days follow up. Sixty-six percent (n = 95) underwent radical nephrectomy and 62.5% (n = 90) developed CKD (stage 3 or higher) postoperatively. We used univariable analysis to screen for predictors of CKD and multivariable logistic regression to identify independent predictors of CKD and their corresponding odds ratios. Interaction terms were introduced to test for effect modification. To protect against over-fitting, we used 10-fold cross-validation technique to evaluate model performance in multiple training and testing datasets. Validation against an independent external cohort was also performed.Of the variables associated with CKD in univariable analysis, the only independent predictors in multivariable logistic regression were patient age (OR = 1.27 per 5 years, 95% CI: 1.07-1.51), preoperative glomerular filtration rate (GFR), (OR = 0.70 per 10 mL/min, 95% CI: 0.56-0.89), and receipt of radical nephrectomy (OR = 4.78, 95% CI: 2.08-10.99). There were no significant interaction terms. The resulting model had an area under the curve (AUC) of 0.798. A 10-fold cross-validation slightly attenuated the AUC to 0.774 and external validation yielded an AUC of 0.930, confirming excellent model discrimination.Patient age, preoperative GFR, and receipt of a radical nephrectomy independently predicted the development of CKD in patients undergoing nephrectomy for kidney cancer in a validated predictive model.

Abstract

To examine contemporary outcomes of minimally invasive radical prostatectomy (MIRP) compared with open prostatectomy, using a national, prospective perioperative database reflecting diverse practice settings.The National Surgical Quality Improvement Program database was queried from 2005 to 2010 for laparoscopic or robotic prostatectomy (Current Procedural Terminology code 55866) and open retropubic prostatectomy (Current Procedural Terminology codes 55840, 55842, 55845). Perioperative outcomes examined were surgical and total operation duration, transfusion rates, length of stay, major morbidity (cardiovascular, pulmonary, renal, and infectious), and mortality.The study identified 5319 radical prostatectomies: 4036 MIRP and 1283 open. Although operative time was significantly longer in the MIRP group, there were significantly fewer perioperative blood transfusions and shorter mean length of stay. Major postoperative morbidity and mortality were 5% in the MIRP group and 9% in the open group (P

Abstract

Photoacoustic imaging is a promising new technology that combines tissue optical characteristics with ultrasound transmission and can potentially visualize tumor depth in bladder cancer. We imaged simulated tumors in 5 fresh porcine bladders with conventional pulse-echo sonography and photoacoustic imaging. Isoechoic biomaterials of different optical qualities were used. In all 5 of the bladder specimens, photoacoustic imaging showed injected biomaterials, containing varying degrees of pigment, better than control pulse-echo sonography. Photoacoustic imaging may be complementary to diagnostic information obtained by cystoscopy and urine cytologic analysis and could potentially obviate the need for biopsy in some tumors before definitive treatment.

Abstract

Abstract Purpose: Using barbed suture represents a novel technical modification in the performance of minimally invasive partial nephrectomy. Our purpose of this study was to evaluate the safety and efficacy of this suture for renorrhaphy during laparoscopic partial nephrectomy (LPN). Patients and Methods: Thirteen consecutive patients underwent LPN using V-Loc™ 180 (Covidien, Dublin, Ireland) suture, and a nonconsecutive control group of 24 patients, matched according to tumor size and R.E.N.A.L. nephrometry score, underwent LPN using absorbable polyglactin suture. All 37 patients underwent LPN performed by a single surgeon. Perioperative and postoperative indicators of morbidity, estimated blood loss, and warm ischemia time (WIT) were compared between the groups. Results: Baseline characteristics including age, body mass index, American Society of Anesthesiologists score, tumor size, laterality, and R.E.N.A.L nephrometry score were identical between the groups. On multivariable analysis, there were no significant differences between the two groups with regard to operative time, estimated blood loss, transfusion rates, rates of surgical complications, and length of hospital stay. However, mean WIT was significantly shorter in the V-Loc group compared with the control group (24.5±5.3 minutes versus 31.9±8.9 minutes, P=.01). Conclusions: The use of V-Loc sutures for renorrhaphy during LPN is safe and feasible and, in our series, significantly reduces WIT. Further studies are needed to corroborate these findings, but these results indicate a promising development in reducing WIT during minimally invasive partial nephrectomy.

Abstract

Tyrosine kinase inhibitors (TKI) have dramatically changed the management paradigm of advanced renal cell carcinoma (RCC) and are increasingly being used preoperatively to achieve cytoreduction.To review our case series of post-TKI surgical procedures to add to the current perioperative efficacy and complication profile.Between October 2006 and February 2010, 14 cytoreductive nephrectomies, radical nephrectomies, and metastectomies were performed after neoadjuvant sunitinib or sorafenib for advanced RCC. During the same time frame, a control group of 73 consecutive patients underwent radical nephrectomy, cytoreductive nephrectomy, or metastectomy in the absence of prior systemic therapy. We compared the incidence of perioperative complications and outcomes after surgical procedures between the two cohorts.Median preoperative renal mass size was 11 cm (6.7-24.2 cm). Primary tumor shrinkage was seen in 57%; median shrinkage was 18% (8%-25%). The median treatment period was 17 weeks, and the median time from TKI discontinuation was 2 weeks. Compared with a control group and after adjusting for confounding covariates, presurgical TKI use was not associated with a significant increase in perioperative complications (50% vs. 40%, P = 0.25) or perioperative bleeding (36% vs. 34%, P = 0.97) but was associated with increased incidence and grade of intraoperative adhesions (86% vs. 58%, P = 0.001; grade 3 vs. 1, P = 0.002).Compared with the published reports, we observed less hemorrhagic and wound healing issues but a significant increase in incidence and severity of intraoperative adhesions, which can present a formidable technical challenge. Potential reasons for our lower complication rate could be increased time from TKI discontinuation to surgery, longer time to postoperative TKI re-initiation, increased use of preoperative angioembolization, and the lack of preoperative bevacizumab administration. Presurgical TKI therapy can permit effective surgical cytoreduction with a safety and complication profile equivalent to that of non-TKI-nephrectomy; however safety data continue to evolve, and preoperative TKI use requires further prospective investigation.

Abstract

The Accordion is a novel endoscopic device that prevents retropulsion of ureteral stones and their fragments during ureteroscopic laser lithotripsy. We describe our experience with its use focusing on three main endpoints: operating time, fluoroscopy time, and stone-free rates.Of 308 consecutive cases of unilateral ureteroscopic laser lithotripsy from 2006-2010, we analyzed 235 cases of ureteral stones. Chart review was performed to document patient demographics (age, sex, and race), stone characteristics (stone size, density, laterality, location, and multiplicity), operative characteristics (use of preoperative and/or postoperative stents, ureteral balloon dilators, ureteral access sheaths, the Holmium laser, and the Accordion device), and surgical outcomes (operative time, fluoroscopy time, stone-free status, and complications).The baseline characteristics between the Accordion and non-Accordion group were statistically similar. In univariate nonparametric tests of medians, Accordion device usage was not associated with a significant reduction in fluoroscopy time (median 1.68 vs. 1.95 minutes, p=0.28) or operating time (median 52.5 vs. 61 minutes, p=0.19). However, the stone-free rate for the Accordion group was significantly higher compared to the non-Accordion group (84.2% vs. 53.6%, p=0.001). In multivariate generalized linear models, Accordion usage was not associated with decreased operating or fluoroscopy times. Accordion use was associated with statistically significant greater odds of stone-free status (odds ratio 4.35, 95% confidence interval 2.36-8.00). Complication severity and rates were comparable between the two groups.The Accordion antiretropulsive device improves stone-free rates during ureteroscopic laser lithotripsy. Prospective studies are needed to validate these results.

Abstract

Current clinical judgment in bladder cancer (BC) relies primarily on pathological stage and grade. We investigated whether a molecular classification of tumor cell differentiation, based on a developmental biology approach, can provide additional prognostic information. Exploiting large preexisting gene-expression databases, we developed a biologically supervised computational model to predict markers that correspond with BC differentiation. To provide mechanistic insight, we assessed relative tumorigenicity and differentiation potential via xenotransplantation. We then correlated the prognostic utility of the identified markers to outcomes within gene expression and formalin-fixed paraffin-embedded (FFPE) tissue datasets. Our data indicate that BC can be subclassified into three subtypes, on the basis of their differentiation states: basal, intermediate, and differentiated, where only the most primitive tumor cell subpopulation within each subtype is capable of generating xenograft tumors and recapitulating downstream populations. We found that keratin 14 (KRT14) marks the most primitive differentiation state that precedes KRT5 and KRT20 expression. Furthermore, KRT14 expression is consistently associated with worse prognosis in both univariate and multivariate analyses. We identify here three distinct BC subtypes on the basis of their differentiation states, each harboring a unique tumor-initiating population.

Abstract

Management for intraparenchymal renal tumors represents a technical challenge during laparoscopic partial nephrectomy since, unlike exophytic tumors, there are no external visual cues on the renal surface to guide tumor localization or excision. Also, hemostatic renorrhaphy and pelvicalyceal suture repair in these completely intrarenal tumors create additional challenges. We examined the safety and technical feasibility of this procedure in this cohort.Of 800 patients who underwent laparoscopic partial nephrectomy 55 (6.9%) had completely intraparenchymal tumors. Technical steps included intraoperative ultrasound guidance of tumor resection, en bloc hilar clamping, cold excision of tumor and sutured renal reconstruction.Mean tumor size was 2.3 cm (range 1.0 to 4.5), mean blood loss was 236 cc (range 25 to 1,000) and mean warm ischemia time was 29.9 minutes (range 7 to 57). There were no positive margins. When we compared laparoscopic partial nephrectomy for intraparenchymal tumors to the same procedure in another 3 tumor groups, including completely exophytic tumors, tumors infiltrating up to sinus fat and tumors infiltrating but not up to sinus fat, there were no statistically significant differences among the groups in complications, positive margin rate, blood loss, or tumor excision or warm ischemia time.Laparoscopic partial nephrectomy for completely intrarenal tumors is a technically advanced but effective, safe procedure. Facility and experience with the technique, effective use of intracorporeal laparoscopic ultrasound and adherence to sound surgical principles are the keys to success. Most recently we have performed laparoscopic and robotic partial nephrectomy for such completely intrarenal tumors using a zero ischemia technique.

Abstract

Study Type - Therapy (case series). Level of Evidence: 4. What's known on the subject? and What does the study add? The exact incidence of splenic injury during laparoscopic urologic procedures is not known; however, it is an uncommon occurrence. Also, the optimal treatment algorithm is not well delineated and the efficacy of successfully treating minor injuries to the spleen without resorting to splenectomy is not well described in the urologic literature. This study outlines the rate of splenic injury during a variety of laparoscopic urologic procedures and we outline a treatment algorithm that has been successfully employed in the management of these patients, which in all cases, did not lead to splenectomy. An important point is also that multiple adjunctive hemostatic measures should be used when a splenic injury is recognized and that a thorough search should ensue when suspicion of an occult splenic injury exists, as an unrecognized splenic injury may lead to severe post operative haemorrhagic complications.• To evaluate incidence, risk factors for, and management of intraoperative splenic injury in our laparoscopic patient cohort.• All patients undergoing laparoscopic urological upper tract procedures at two institutions between January 2001 and April 2006 and January 2000 and December 2008, respectively, were retrospectively examined for complications. • From these patients, those with intraoperative splenic injuries were selected and examined. • Possible factors predisposing patients to splenic injury were evaluated and the management plan for each patient was analysed to identify optimal treatment efficacy.• Of 2620 patients undergoing upper tract urological laparoscopic surgery, 14 patients (0.5%) sustained splenic injury and underwent left-sided surgery, 13 via a transperitoneal approach. • In 12 of the 14 patients, the splenic injury was recognized intraoperatively and all were effectively managed laparoscopically with a combination of argon beam coagulation, biological haemostatic agent FloSeal(TM) (Baxter, Deerfield, IL, USA), and bio-absorbable Surgicel® (Johnson and Johnson, Somerville, NJ, USA); none of these patients required splenectomy or developed any postoperative complications. • In two patients, the splenic injury was not recognized intraoperatively; both patients presented with delayed haemorrhage necessitating open splenectomy in each instance.• Splenic injuries are uncommon during laparoscopic urological surgery, but when a significant splenic injury occurs, it can be effectively managed laparoscopically, using conservative measures, without need for splenectomy. • If the splenic injury is not recognized intraoperatively, delayed haemorrhage is likely to occur necessitating emergent re-exploration and splenectomy. • Prompt and accurate intraoperative diagnosis of splenic injury is critical for achieving a good outcome.

Abstract

A recent increase in the detection of contrast enhancing renal masses 4 cm or smaller suspicious for malignancy has led to the widespread use of nephron sparing options. Limited data exist to help clinicians decide which of these competing nephron sparing therapies is most appropriate. We performed a cost-effectiveness analysis to evaluate the relative clinical and economic merits of commonly available nephron sparing strategies for small renal masses.We developed a decision analytic Markov model estimating the costs and health outcomes of treating a healthy 65-year-old patient with an asymptomatic unilateral small renal mass using competing nephron sparing options of immediate intervention (ie open and laparoscopic partial nephrectomy as well as laparoscopic and percutaneous ablation), active surveillance with possible delayed intervention and nonsurgical management with observation. Benefits were measured in quality adjusted life-years. We used a societal perspective, lifetime horizon and willingness to pay threshold of $50,000 per quality adjusted life-year gained. Model results were assessed with sensitivity analyses.In the base case scenario the least costly option was observation and the optimal option was immediate laparoscopic partial nephrectomy, which had an incremental cost-effectiveness ratio of $36,645 per quality adjusted life-year gained compared to surveillance with possible delayed percutaneous ablation. Results were sensitive to age at diagnosis, health status and tumor size.Immediate laparoscopic partial nephrectomy is the preferred nephron sparing option for healthy patients younger than 74 years old with a small renal mass. Surveillance with possible delayed percutaneous ablation is a cost-effective alternative for patients with advanced age or significant comorbidities. Observation maximizes quality adjusted life-years in patients who are poor surgical candidates or with limited life expectancy (less than 3 years).

Abstract

Tumor volume and percent cancer (ratio of tumor volume/prostate volume) have been proposed as predictors of biochemical recurrence and cancer specific survival after radical prostatectomy. However, their relative merits as prognosticators have not been tested. We therefore evaluated and compared tumor volume and percent cancer as independent predictors of biochemical recurrence and prostate cancer specific death after radical prostatectomy.A retrospective review of 739 patients who underwent radical prostatectomy for prostate cancer between 1984 and 2004 was conducted. Median follow-up was 91.7 months, and 22 patients died of prostate cancer. Univariate and multivariate analysis evaluated the following factors in predicting biochemical recurrence and prostate cancer specific death: tumor volume, prostate volume, percent cancer, Gleason score, percentage of Gleason grade 4/5, margin status, capsular invasion status, seminal vesicle invasion status, preoperative PSA, and lymph node status.In univariate analysis, both tumor volume (P<0.001) and percent cancer (P<0.001) significantly correlated with biochemical recurrence. Since they are highly correlated, they did not predict outcome independently when included in the same model; however, both were highly predictive for biochemical recurrence in separate multivariate models (P=0.01 for both). Both also correlated with cancer specific survival as single variables; however, in separate multivariate models, only tumor volume (P=0.03) predicted death, while percent cancer did not (P=0.09).Tumor volume and percent cancer are independent predictors of recurrence after radical prostatectomy. However, in our series, tumor volume predicted cancer specific death better than percent cancer. Therefore, accurate determination of tumor volume, along with other accepted pathologic indices, is sufficient and preferred over percent cancer for prognostication after radical prostatectomy.

Abstract

The use of surgical clips as suture anchors has made laparoscopic partial nephrectomy (LPN) technically simpler by eliminating the need for intracorporeal knot tying. However, the holding strength of these clips has not been analyzed in the human kidney. Therefore, the safety of utilizing suture anchors is unknown as the potential for clip slippage or renal capsular tears during LPN could result in postoperative complications including hemorrhage and urinoma formation. With the above in mind, we sought to compare the ability of Lapra-Ty clips and Hem-o-lok clips to function as suture anchors on human renal capsule.Fresh human cadaveric kidneys with intact renal capsules were obtained. A Lapra-Ty clip (Ethicon, Cincinnati, OH) or a Hem-o-lok clip (Weck, Raleigh, NC) was secured to a no. 1 Vicryl suture (Ethicon) with and without a knot, as is typically utilized during the performance of LPN. The suture was then placed through the renal capsule and parenchyma and attached to an Imada Mechanical Force Tester (Imada, Northbrook, IL). The amount of force required both to violate the renal capsule and to dislodge the clip was recorded separately.Six Lapra-Ty clips and six Hem-o-lok clips were tested. The mean force in newtons required to violate the renal capsule for the Lapra-Ty group was 7.33 N and for the Hem-o-lok group was 22.08 N (p < 0.001). The mean force required to dislodge the clip from the suture for the Lapra-Ty group was 9.0 N and for the Hem-o-lok group was 3.4 N (p < 0.001). When two Hem-o-lok clips were placed on the suture in series, the mean force required to dislodge the clips was 10.6 N.When compared with Lapra-Ty clips, using two Hem-o-lok clips may provide a more secure and cost-effective method to anchor sutures on human renal capsule when performing LPN.

Abstract

Laparoscopic radical nephrectomy of a pelvic kidney for renal cell carcinoma is a procedure with little precedent, but one that offers the advantages of the minimally invasive approach. We present our experience with this unique procedure.A 64-year-old male with a history of end-stage renal disease was diagnosed with a 2.6-cm enhancing mass in a pelvic left kidney with 2 separate sources of blood supply. He was offered either an open radical nephrectomy or a laparoscopic radical nephrectomy and opted for the minimally invasive approach.The procedure was performed successfully without complications and with minimal blood loss. The case was marked both by difficulty in mobilizing the sigmoid colon and the limited working space of the pelvis, which made localization of the numerous hilar vessels challenging.Laparoscopic radical nephrectomy for a pelvic ectopic kidney appears to be safe and efficacious. Success is dependent on familiarity with pelvic anatomy, optimal port placement, and preprocedure knowledge of the often-complicated vascular anatomy of the ectopic kidney. Preoperative imaging to delineate anomalous vascular anatomy is mandatory, and ureteral catheter placement is helpful for intraoperative identification purposes.

Abstract

A 57-year-old woman presented to the emergency department at a community hospital with a 2-month history of fatigue and right-sided flank and abdominal pain. Noncontrast CT of the abdomen and pelvis revealed a 9.1 cm right renal mass.Contrast CT of the chest, abdomen and pelvis, MRI of the abdomen and pelvis with gadolinium, radionuclide bone scan, lung nodule biopsy, complete blood count, comprehensive metabolic profile, and measurement of serum lactate dehydrogenase.Stage IV, T3bN0M1 clear cell renal cell carcinoma, with an associated tumor thrombus extending into the vena cava.The patient was treated with neoadjuvant sunitinib, which resulted in a marked response in the primary tumor and metastatic lesions as well as regression of the tumor thrombus well into the renal vein. Thus, laparoscopic radical nephrectomy was feasible and was achieved without hemorrhagic or wound healing complications. One month after surgery, she had evidence of disease progression in the lung and a periaortic lymph node. She was restarted on sunitinib with resultant disease stabilization, but discontinued the drug owing to toxicity. Eight months after cessation of sunitinib, she received a dendritic cell vaccine. She remains alive without evidence of disease progression 2 years after her diagnosis.

Abstract

Nutcracker syndrome is a rare entity caused by extrinsic compression on the left renal vein as it crosses between the superior mesenteric artery and the aorta. It can clinically present with flank pain and hematuria. Accepted treatments include open vascular bypass procedures or endoluminal stenting. We present the first description, to our knowledge, of a laparoscopic splenic vein-left renal vein bypass to relieve the outflow obstruction. The patient, a 29-year-old woman with debilitating left flank pain, presented with nutcracker syndrome. Left renal vein outflow was obstructed at the level of the intersection between the aorta and the superior mesenteric artery. The option of laparoscopic splenic to left renal vein bypass was discussed and performed. A five-port transperitoneal approach was used. Meticulous vascular control was achieved with numerous laparoscopic vascular bulldog clamps. With completely intracorporeal suturing techniques, the splenic vein was anastomosed to the superior aspect of the anterior left renal vein. Total warm ischemia time was 37 minutes. The anastomosis was watertight immediately upon unclamping. Interestingly, upon unclamping, the luminal diameter of the splenic vein appeared to increase to twice its native diameter. The proximal left renal vein appeared less distended, indicating preferential venous outflow through the newly created venous bypass. Blood loss was minimal, no intraoperative or postoperative complications occurred, and the patient's symptoms improved. This report continues to augment the indications for laparoscopic surgery in even complex, urologic vascular situations.

Abstract

A retrocaval ureter is a rare entity that has traditionally been treated with open pyeloplasty techniques. In this paper, we describe the successful performance of a laparoscopic dismembered pyeloplasty for a retrocaval ureter and present important technical points. In reviewing the available literature about this technique, the laparoscopic approach should be considered to be first-line treatment for this anatomic anomaly due to the good track record, quick convalescence, and relative technical ease.

Abstract

The field of endourology, which encompasses genitourinary endoscopy and percutaneous, laparoscopic, and robotic surgery, has advanced rapidly over the past quarter century, causing endourology to be considered a subspecialty of urology. The Endourological Society, which is recognized by the American Urological Association, offers numerous clinical and research fellowship opportunities throughout the world. The decision to seek postresidency fellowship training in endourology is complex as is the process of seeking subsequent employment. We offer guidance on the decision-making process to obtain fellowship training as well as on early steps into subsequent academic or private practice settings.

Abstract

To compare the outcomes of percutaneous nephrolithotomy (PCNL) and ureterorenoscopy (URS) for 1- to 2-cm renal calculi with specific reference to the stone clearance rate and morbidity.The records of 27 patients who underwent either PCNL (N = 15) or URS (N = 12) by standard techniques over an 8-month period for renal calculi between 1 and 2 cm were reviewed retrospectively. Demographic, intraoperative, and postoperative data were accrued and compared to identify any statistically significant differences. The median stone burden was slightly but not significantly higher in the PCNL group (1.8 cm v 1.25 cm; P = 0.19). Postoperative plain films were used to confirm stone clearance.The procedure was technically successful in all 27 patients. No patient in either group required a repeat session or ancillary procedure. All 15 PCNL procedures were completed through a single percutaneous tract. The PCNL and URS groups were equivalent with respect to operative time (79.0 minutes v 68.5 minutes) and incidence of complications (2 v 0). No patient in either group had significant hemorrhage or required blood transfusion. The overall stone-free rate was 87% for PCNL and 67% for URS (P = 0.36).Both PCNL and URS are effective options for renal calculi between 1 and 2 cm. The stonefree and complication rates for PCNL are higher, but the differences were not statistically significant in our series. The operative times are statistically equivalent, despite the potentially longer fragmentation times required for URS. The choice of treatment ultimately depends on the individual surgeon's preference and level of expertise.

Abstract

To evaluate the feasibility of high-resolution optical coherence tomography (OCT) in the identification of neurovascular bundles (NVBs) during laparoscopic and robotic radical prostatectomy (LRP).Between November 2005 and March 2006, 24 patients undergoing transperitoneal laparoscopic or robotic radical prostatectomy were enrolled in this study. Once the bladder was taken down and the prostate mobilized, the Niris imaging system was deployed. In each patient, in-vivo images were obtained to determine the image characteristics of NVBs, adipose tissue, prostate capsule, and endopelvic fascia. The NVB was imaged again in vivo, after the prostate was excised. Ex-vivo images were obtained from the prostate surface to look for the presence or absence of the NVBs and correlated with the surgeon's assessment of the adequacy of nerve sparing.From 24 patients, we obtained more than 300 OCT images of tissue structures including endopelvic fascia, prostate capsule, NVBs, fat, lateral pedicles, and lymphatics. These images were found to correlate independently with the surgeon's impression of the tissue being imaged. Preliminary comparison with parallel histologic evaluation was performed in four patients that suggested OCT could help to identify the NVBs and prostate capsule during LRP.In our preliminary experience with the Niris system during LRP, OCT was able to image the NVB in all patients. This could enhance surgical precision during nerve sparing and positively impact potency rates after radical prostatectomy. Further research will be needed, including parallel histologic evaluation and follow-up, to validate the findings of OCT imaging.

Abstract

Ileal and intestinal ureteral replacement remains a useful procedure for complex ureteral reconstruction. We examined the long-term safety and efficacy of this procedure, especially in regard to maintaining preoperative renal function and the avoidance of major complications.A total of 56 patients underwent intestinal ureteral substitution at our institution between 1979 and 2003, including 52 with an ileal ureteral replacement, 2 with colonic replacement alone and 2 with bilateral ureteral replacement, necessitating ileum and colon for 1 ureter each. The factors reviewed were indications for surgery, type of ureteral replacement, and the presence and type of complications. Followup data included excretory urogram or equivalent imaging results, and measurement of serum chloride, bicarbonate and creatinine before and after the procedure.Overall the complication rate remained low. Mean followup was 6.04 years (median 3.2). Most postoperative complications, which occurred in 10 patients (17.9%), were minor in nature, including pyelonephritis, fever of unknown origin, neuroma, hernia, recurrent urolithiasis and deep venous thrombosis. Major complications occurred in 6 patients (10.5%), including anastomotic stricture, ileal graft obstruction, wound dehiscence and chronic renal failure. Overall patients did not experience worsening renal function after the procedure with equivalent median creatinine before and after the procedure (1.0 mg/dl).During long-term followup major complications are rare and renal function remains preserved. Ileal and intestinal ureteral substitution remains a safe and efficacious procedure in patients with complex and difficult ureteral issues not amenable to more conservative measures.

Abstract

In this investigation, we examined the role of the Axl proto-oncogene in renal cell carcinoma (RCC). Axl is a tyrosine kinase receptor implicated in myeloid leukogenesis, and has been found to be overexpressed in lung cancers and breast cancers. Axl has been described to act as a mitogenic factor along with its ligand Gas-6. Axl has also shown to have a role in apoptosis, cell adhesion, and chemotaxis. The differential expression of the Axl RNA transcript was examined in 20 pairs of matched normal kidney and clear cell RCC patient samples. We found that there was a significant increase in the steady-state levels of Axl mRNA in the RCC compared with the normal kidney pair (Student's paired t-test P < 0.001). There was also a significant increase in Axl expression overall in RCC compared to normal kidney (P < 0.03). Western blotting was utilized to determine Axl protein levels in six out of the 20 pairs of the normal/RCC matched pairs. Overall, the level of expression was not significantly different between the paired normal kidneys and kidney tumors, but the detected Axl protein appeared to be at slightly different molecular weights. Primers were constructed for the two known Axl variant, RT-PCR performed, but no differences were observed in the expression of each variant. Next, we performed a gene silencing experiment utilizing double-stranded RNA constructed to silence the Axl gene in the 293 transformed kidney cell line. There was a 50% decrease in Axl gene expression in the RNAi transfected over control cells. In addition, flow cytometry performed to determine DNA content showed a 30% increase in G1/G0 cells, which were transfected with axl RNAi compared to control. Altogether, these findings suggest an overexpression of Axl as part of a proliferative phenotype in RCC.

Abstract

Accepted management of vesicoureteral reflux includes surgical correction or prophylactic antibiotics with the hope for resolution as the child grows. The physician must consider surgery when reflux does not resolve despite uneventful years on prophylactic antibiotics. An alternative is cessation of the antibiotics. We report on the outcome of children taken off antibiotics with persistent reflux.During a 14-year period 51 children with documented reflux were taken off antibiotic prophylaxis. Selection criteria included children who were old enough to verbalize the symptoms of a urinary tract infection, and had normal voiding patterns, a minor history of infections and minimal or no renal scarring. Routine followup included nuclear cystography and renal sonography.A total of 40 girls and 11 boys maintained on antibiotics for a mean of 4.8 years were taken off prophylaxis and followed for an average of 3.7 years. Mean patient age when prophylactic antibiotics were stopped was 8.6 years. Reflux resolved in 10 children (19.6%). A urinary tract infection developed in 5 girls and 1 boy (11.8%) (mean age 11) an average of 2.3 years (range 4 months to 9.4 years) after antibiotic discontinuation. One child had symptoms consistent with cystitis and 5 had febrile urinary tract infections. All were treated with oral antibiotics and 5 had subsequent operations. No new renal scars developed.The majority of children did well following cessation of antibiotic prophylaxis despite persistent vesicoureteral reflux. Cessation of antibiotic prophylaxis is a reasonable option in a highly select patient population with reflux.